河岸生态护坡措施水土保持效益的模拟试验研究

[目的]研究不同河岸生态护坡措施的减流、减沙和抑制养分流失的效果,并筛选出较优配置的河流生态护坡模式,为华北地区生态治河实践提供参考。[方法]采用人工降雨试验,测定模拟河流岸坡不同植被护坡措施的径流量、产沙量、养分流失量,分析不同雨强、不同坡度、不同植被措施条件下的减流、减沙和减少养分流失效果;通过主成分分析对9个不同措施试验槽的减流、减沙和减少养分流失效果进行评价。[结果]高羊茅减流减沙效果最优,小冠花减少养分流失效果最优。河岸坡30o、堤顶坡度小于0o的岸坡宜采用高羊茅进行防护;河岸坡45o、堤顶坡度18o的岸坡宜采用小冠花进行防护;河岸坡45o、堤顶坡度0o的岸坡宜采用高羊茅进行防护。[结论]综合来看高羊茅减流减沙效果最好,小冠花次之;小冠花减少养分流失效果最好,紫穗槐次之。

Simulated Research on Soil and Water Conservation Benefits of Riparian Ecological Slope Protection Measures

[Objective] Appropriate measures on riverbank slope were significant for soil and water conservation, water purification, and the health of riparian ecosystem. Artificial rainfall experiment was used to study the dynamics of runoff, sediment yield and nutrient loss.[Methods] The effects of rainfall intensity, slope gradient and protective measures were analyzed. Altogether, nine experimental plots were set and principal component analysis method was used to find the slope protection design which produced the best protective effect.[Results] Tall fescue was most effective on runoff and sediment reduction, while crown vetch had the largest effect in reducing nutrient loss. On slopes with riparian gradient of 30° or 45°, and with 0° or less crest, tall fescue should be used for slope protection. On slope with gradient of 45°and crest of 18°, Crown varia was appropriate for slope protection.[Conclusion] Tall fescue was most effective on runoff and sediment reduction, followed by crown vetch. Crown vetch was the most effective on reducing nutrient loss.